Many people experience breathing problems on a recurring basis, which often result in sleep disordered breathing (i.e., difficulty sleeping, snoring, or other more serious conditions such as obstructive sleep apnea). As technology advances, people with such breathing problems demand increased performance and comfort. Previous devices for improving a user's breathing have included face masks, nose masks, or nasal inserts that help deliver air to the user's nose at positive pressure. These devices help force open the user's breathing passage and thereby improve the user's breathing. However, previous devices have often provided an inadequate fit and thus have caused discomfort for users and failed to adequately prevent leakage.